1. Field of the Invention
The present invention relates to a substrate processing apparatus and method for supplying a developer, a rinsing liquid and the like to substrates such as semiconductor wafers and glass substrates for liquid crystal display panels and for plasma display panels. And it relates especially to a developing apparatus and developing method for developing a thin resist film formed on those substrates and having a predetermined pattern exposed.
2. Description of the Background Art
Conventionally, developing apparatuses of this type comprise a developer supply nozzle having a slit developer discharge unit formed with an opening width equal to or greater than the width of a substrate, and a rinsing liquid supply nozzle having a slit rinsing liquid discharge unit formed with an opening width equal to or greater than the width of a substrate (refer to, for example, U.S. Pat. No. 6,092,937 and Japanese Patent Application Laid-open No. 10-340836).
Such developing apparatuses move the developer supply nozzle from one end of a substrate to the other to supply a developer to the entire upper surface of the substrate (this developer supply method is also called a slit scan developing method), and after the expiration of a predetermined time interval, move the rinsing liquid supply nozzle from one end of the substrate to the other with the same travel speed as the developer supply nozzle to supply a rinsing liquid to the entire upper surface of the substrate and thereby to stop development on the upper surface of the substrate.
In this case, making equal the travel speeds of the developer supply nozzle and the rinsing liquid supply nozzle carries the advantages that development time is approximately the same at each point on the upper surface of the substrate, thereby preventing unevenness in development, and that uniformity in the line width of a resist pattern after development can be improved.
However, in the above developing apparatuses, for reasons such as adhesion of undesirable matter to the discharge units and any possible defects resulting therefrom, the supply of a rinsing liquid from the slit discharge unit may not be uniform (for example, in amount and in velocity) along a discharge width of the discharge unit. The same can be said of the supply of a developer, but since especially a rinsing liquid needs to be passed over a layer of developer, the spacing between the rinsing liquid supply nozzle and the substrate becomes greater and, as a result, there is a greater likelihood that the supply of a rinsing liquid is not uniform.
In this case, since the rinsing liquid supply nozzle and the like are moved linearly from one end of the substrate to the other, a streak of area to which processing liquids were not supplied may remain along a direction of nozzle movement on the substrate, and therefore, the supply of a rinsing liquid and the like to the substrate may become nonuniform along the width of the substrate.
The present invention is directed to an apparatus and method for supplying a developer and a rinsing liquid to a substrate.
A developing apparatus for developing a thin resist film with a developer and stopping development with a rinsing liquid, the resist film being formed on a major surface of a substrate and having a predetermined pattern exposed, includes a substrate holder, a developer supply section, a rinsing liquid supply nozzle, a rinsing liquid supply system and a rinsing liquid supply nozzle moving section. The substrate holder is configured to hold a substrate. The developer supply section is configured to supply a developer to the major surface of the substrate held by the substrate holder to form a developer layer on the major surface of the substrate. The rinsing liquid supply nozzle has a rinsing liquid discharge unit for discharging a rinsing liquid with a discharge width substantially equal to or greater than the width of the substrate. The rinsing liquid supply system is configured to supply a rinsing liquid to the rinsing liquid supply nozzle and to cause the rinsing liquid supply nozzle to discharge a rinsing liquid from the rinsing liquid discharge unit. The rinsing liquid supply nozzle moving section is configured to move the rinsing liquid supply nozzle along a line running diagonally relative to a virtual scanning direction from a supply start point on one end of the substrate held at rest by the substrate holder to a supply end point on the other end of the substrate, so that the rinsing liquid supply nozzle passes over the developer layer on the major surface of the substrate in such a position that a direction along the discharge width of the rinsing liquid discharge unit is substantially perpendicular to the virtual scanning direction. In the development apparatus, the rinsing liquid supply nozzle is moved from the supply start point of the substrate to the supply end point by the rinsing liquid supply nozzle moving section and is at the same time caused to discharge a rinsing liquid from the rinsing liquid discharge unit onto the developer layer by the rinsing liquid supply system.
Shifting the rinsing liquid discharge unit in a direction substantially perpendicular to the virtual scanning direction improves uniformity in the supply of a rinsing liquid.
The present invention is also directed to a developing apparatus for developing a thin resist film with a developer and stopping development with a rinsing liquid, the resist film being formed on the major surface of a substrate and having a predetermined pattern exposed. The development apparatus includes a substrate holder, a substrate rotating section, a developer supply section, a rinsing liquid supply nozzle, a rinsing liquid supply system, a rinsing liquid supply nozzle rotating section and a controller. The substrate holder is configured to hold a substrate. The substrate rotating section is configured to rotate the substrate held by the substrate holder. The developer supply section is configured to supply a developer to the major surface of the substrate held by the substrate holder to form a developer layer on the major surface of the substrate. The rinsing liquid supply nozzle has a rinsing liquid discharge unit for discharging a rinsing liquid with a discharge width substantially equal to or greater than the width of the substrate. The rinsing liquid supply system is configured to supply a rinsing liquid to the rinsing liquid supply nozzle and to cause the rinsing liquid supply nozzle to discharge a rinsing liquid from the rinsing liquid discharge unit. The rinsing liquid supply nozzle rotating section is configured to support one end of the rinsing liquid supply nozzle so that the rinsing liquid supply nozzle is rotatable on a rotation axis outside the substrate held by the substrate holder, and to rotate the rinsing liquid supply nozzle so that the rinsing liquid supply nozzle passes over the substrate held by the substrate holder. The controller is configured to control the substrate rotating section, the rinsing liquid supply system and the rinsing liquid supply nozzle rotating section so that the substrate held by the substrate holder is rotated in a first rotational direction by the substrate rotating section, and so that the rinsing liquid supply nozzle, while being rotated in the first rotational direction to pass over the developer layer formed on the major surface of the substrate being rotated, discharges a rinsing liquid from the rinsing liquid discharge unit to supply a rinsing liquid from a supply start point on one end of the substrate to a supply end point on the other end.
With a substrate being rotated, the rinsing liquid supply nozzle is rotated to pass over the substrate and at the same time to supply a rising liquid to the major surface of the substrate. That is, the rinsing liquid supply nozzle moves along an arc relative to the substrate, which improves uniformity in the supply of a rinsing liquid.
In the developing apparatus, the controller controls the substrate rotating section and the rinsing liquid supply nozzle rotating section so that a virtual scanning direction from the supply start point of the substrate to the supply end point is substantially perpendicular to a direction along the discharge width of the rinsing liquid discharge unit.
Preferably, control of the controller is made such that a velocity of the developer supply nozzle when moving over the substrate and, out of relative velocity components of the rinsing liquid supply nozzle with respect to the substrate being rotated by the substrate rotating section, a relative velocity component in a virtual scanning direction from the supply start point of the substrate to the supply end point have substantially the same constant velocity pattern.
Since the velocity of the developer supply nozzle and the relative velocity component of the rinsing liquid supply nozzle in the virtual scanning direction have substantially the same constant velocity pattern, the timing of termination of the development can be made approximately the same at each point in the plane of the substrate and also the amounts of the supply of a developer and a rinsing liquid can be made approximately uniform.
More preferably, a rinsing liquid is discharged from the rinsing liquid discharge unit in a direction opposite to a direction of movement of the rinsing liquid supply nozzle relative to a substrate. And, at a point in time when a rinsing liquid discharged from the rinsing liquid discharge unit drops onto the developer layer on the major surface of the substrate, out of relative velocity components of the rinsing liquid with respect to the substrate, a relative velocity component in a direction of its discharge with respect to a direction of a plane of the substrate is set to be greater than 0.
Since the relative velocity component of the rising liquid in the direction of its discharge with respect to the plane of the substrate is set to be greater than 0, it is possible to prevent the occurrence of such situations that a rinsing liquid is swept in front of the rinsing liquid supply nozzle.
The present invention is also directed a developing method for developing a thin resist film with a developer and stopping development with a rinsing liquid, the resist film being formed on a major surface of a substrate and having a predetermined pattern exposed. The developing method includes the steps of: (a) supplying a developer onto the major surface of a substrate to form a developer layer on the major surface; (b) discharging a rinsing liquid onto the developer layer from a rinsing liquid discharge unit with a discharge width substantially equal to or greater than the width of the substrate; (c) while keeping the rinsing liquid discharge unit in such a position that a direction along the discharge width of the rinsing liquid discharge unit is substantially perpendicular to a virtual scanning direction from a supply start point on one end of the substrate to the supply end point on the other end, relatively moving the rinsing liquid discharge unit from the supply start point of the substrate to the supply end point; and (d) shifting the rinsing liquid discharge unit in a direction substantially perpendicular to the virtual scanning direction. The steps (b) through (d) are performed in parallel after the step (a).
Shifting the rinsing liquid discharge unit in a direction orthogonal to the virtual scanning direction improves uniformity in the supply of a rinsing liquid.
Thus, an object of the present invention is to improve uniformity in the supply of a rinsing liquid.
These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.